linux_dsm_epyc7002/net
Eric Dumazet 6c0afef5fb ipv6/flowlabel: wait rcu grace period before put_pid()
syzbot was able to catch a use-after-free read in pid_nr_ns() [1]

ip6fl_seq_show() seems to use RCU protection, dereferencing fl->owner.pid
but fl_free() releases fl->owner.pid before rcu grace period is started.

[1]

BUG: KASAN: use-after-free in pid_nr_ns+0x128/0x140 kernel/pid.c:407
Read of size 4 at addr ffff888094012a04 by task syz-executor.0/18087

CPU: 0 PID: 18087 Comm: syz-executor.0 Not tainted 5.1.0-rc6+ #89
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 pid_nr_ns+0x128/0x140 kernel/pid.c:407
 ip6fl_seq_show+0x2f8/0x4f0 net/ipv6/ip6_flowlabel.c:794
 seq_read+0xad3/0x1130 fs/seq_file.c:268
 proc_reg_read+0x1fe/0x2c0 fs/proc/inode.c:227
 do_loop_readv_writev fs/read_write.c:701 [inline]
 do_loop_readv_writev fs/read_write.c:688 [inline]
 do_iter_read+0x4a9/0x660 fs/read_write.c:922
 vfs_readv+0xf0/0x160 fs/read_write.c:984
 kernel_readv fs/splice.c:358 [inline]
 default_file_splice_read+0x475/0x890 fs/splice.c:413
 do_splice_to+0x12a/0x190 fs/splice.c:876
 splice_direct_to_actor+0x2d2/0x970 fs/splice.c:953
 do_splice_direct+0x1da/0x2a0 fs/splice.c:1062
 do_sendfile+0x597/0xd00 fs/read_write.c:1443
 __do_sys_sendfile64 fs/read_write.c:1498 [inline]
 __se_sys_sendfile64 fs/read_write.c:1490 [inline]
 __x64_sys_sendfile64+0x15a/0x220 fs/read_write.c:1490
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458da9
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f300d24bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000458da9
RDX: 00000000200000c0 RSI: 0000000000000008 RDI: 0000000000000007
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000005a R11: 0000000000000246 R12: 00007f300d24c6d4
R13: 00000000004c5fa3 R14: 00000000004da748 R15: 00000000ffffffff

Allocated by task 17543:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_kmalloc mm/kasan/common.c:497 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505
 slab_post_alloc_hook mm/slab.h:437 [inline]
 slab_alloc mm/slab.c:3393 [inline]
 kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3555
 alloc_pid+0x55/0x8f0 kernel/pid.c:168
 copy_process.part.0+0x3b08/0x7980 kernel/fork.c:1932
 copy_process kernel/fork.c:1709 [inline]
 _do_fork+0x257/0xfd0 kernel/fork.c:2226
 __do_sys_clone kernel/fork.c:2333 [inline]
 __se_sys_clone kernel/fork.c:2327 [inline]
 __x64_sys_clone+0xbf/0x150 kernel/fork.c:2327
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 7789:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467
 __cache_free mm/slab.c:3499 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3765
 put_pid.part.0+0x111/0x150 kernel/pid.c:111
 put_pid+0x20/0x30 kernel/pid.c:105
 fl_free+0xbe/0xe0 net/ipv6/ip6_flowlabel.c:102
 ip6_fl_gc+0x295/0x3e0 net/ipv6/ip6_flowlabel.c:152
 call_timer_fn+0x190/0x720 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers kernel/time/timer.c:1681 [inline]
 __run_timers kernel/time/timer.c:1649 [inline]
 run_timer_softirq+0x652/0x1700 kernel/time/timer.c:1694
 __do_softirq+0x266/0x95a kernel/softirq.c:293

The buggy address belongs to the object at ffff888094012a00
 which belongs to the cache pid_2 of size 88
The buggy address is located 4 bytes inside of
 88-byte region [ffff888094012a00, ffff888094012a58)
The buggy address belongs to the page:
page:ffffea0002500480 count:1 mapcount:0 mapping:ffff88809a483080 index:0xffff888094012980
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea00018a3508 ffffea0002524a88 ffff88809a483080
raw: ffff888094012980 ffff888094012000 000000010000001b 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888094012900: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
 ffff888094012980: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
>ffff888094012a00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
                   ^
 ffff888094012a80: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc
 ffff888094012b00: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc

Fixes: 4f82f45730 ("net ip6 flowlabel: Make owner a union of struct pid * and kuid_t")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-29 23:30:13 -04:00
..
6lowpan 6lowpan: fix debugfs_simple_attr.cocci warnings 2019-01-22 09:51:19 +01:00
9p 9p/net: fix memory leak in p9_client_create 2019-03-13 11:50:04 +01:00
802
8021q vlan: conditional inclusion of FCoE hooks to match netdevice.h and bnx2x 2019-04-04 17:18:34 -07:00
appletalk appletalk: Fix potential NULL pointer dereference in unregister_snap_client 2019-03-15 11:25:48 -07:00
atm net: atm: Fix potential Spectre v1 vulnerabilities 2019-04-16 21:01:45 -07:00
ax25 ax25: fix possible use-after-free 2019-01-23 11:18:00 -08:00
batman-adv batman-adv: Fix genl notification for throughput_override 2019-03-25 09:31:19 +01:00
bluetooth Bluetooth: Check address length before reading address field 2019-04-12 10:25:03 -07:00
bpf bpf: fix warning about using plain integer as NULL 2019-03-08 21:17:07 +01:00
bpfilter bpfilter: re-add header search paths to tools include to fix build error 2019-02-23 13:34:40 -08:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2019-04-22 21:23:55 -07:00
caif net: caif: use skb helpers instead of open-coding them 2019-02-17 11:01:17 -08:00
can can: bcm: check timer values before ktime conversion 2019-01-22 11:33:46 +01:00
ceph libceph: fix breakage caused by multipage bvecs 2019-03-25 22:28:07 +01:00
core socket: fix compat SO_RCVTIMEO_NEW/SO_SNDTIMEO_NEW 2019-04-16 21:52:22 -07:00
dcb net: dcb: Add priority-to-DSCP map getters 2018-07-27 13:17:50 -07:00
dccp dccp: Fix memleak in __feat_register_sp 2019-04-01 18:15:10 -07:00
decnet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-29 21:18:54 -08:00
dns_resolver dns: Allow the dns resolver to retrieve a server set 2018-10-04 09:40:52 -07:00
dsa net: dsa: Implement flow_dissect callback for tag_qca 2019-03-28 16:57:19 -07:00
ethernet net/ethernet: Add parse_protocol header_ops support 2019-02-22 12:55:31 -08:00
hsr net/hsr: fix possible crash in add_timer() 2019-03-07 11:02:08 -08:00
ieee802154 net: remove unused struct inet_frag_queue.fragments field 2019-02-26 08:27:05 -08:00
ife
ipv4 tcp: add sanity tests in tcp_add_backlog() 2019-04-29 23:20:37 -04:00
ipv6 ipv6/flowlabel: wait rcu grace period before put_pid() 2019-04-29 23:30:13 -04:00
iucv iucv: Remove SKB list assumptions. 2018-11-10 16:55:11 -08:00
kcm kcm: switch order of device registration to fix a crash 2019-04-01 14:59:20 -07:00
key af_key: unconditionally clone on broadcast 2019-02-12 10:36:42 +01:00
l2tp l2tp: use rcu_dereference_sk_user_data() in l2tp_udp_encap_recv() 2019-04-26 11:18:23 -04:00
l3mdev l3mdev: add function to retreive upper master 2018-12-03 14:15:26 -08:00
lapb
llc llc: Check address length before reading address field 2019-04-12 10:25:03 -07:00
mac80211 mac80211: don't attempt to rename ERR_PTR() debugfs dirs 2019-04-23 13:47:05 +02:00
mac802154 mac802154: Remove VLA usage of skcipher 2018-09-28 12:46:07 +08:00
mpls mpls: Fix 6PE forwarding 2019-03-19 16:00:22 -07:00
ncsi net/ncsi: handle overflow when incrementing mac address 2019-04-23 21:15:15 -07:00
netfilter netfilter: fix nf_l4proto_log_invalid to log invalid packets 2019-04-22 10:38:50 +02:00
netlabel netlabel: fix out-of-bounds memory accesses 2019-02-27 21:45:24 -08:00
netlink genetlink: use idr_alloc_cyclic for family->id assignment 2019-04-26 11:59:58 -04:00
netrom net: netrom: Fix error cleanup path of nr_proto_init 2019-04-11 13:59:49 -07:00
nfc NFC: nci: Add some bounds checking in nci_hci_cmd_received() 2019-04-06 15:05:07 -07:00
nsh
openvswitch openvswitch: fix flow actions reallocation 2019-03-28 17:15:44 -07:00
packet net/packet: Set __GFP_NOWARN upon allocation in alloc_pg_vec 2019-03-20 10:46:50 -07:00
phonet phonet: fix building with clang 2019-02-21 16:23:56 -08:00
psample
qrtr mm: replace all open encodings for NUMA_NO_NODE 2019-03-05 21:07:14 -08:00
rds net: rds: exchange of 8K and 1M pool 2019-04-24 12:07:08 -07:00
rfkill rfkill: gpio: Remove unused include 2018-12-18 13:13:56 +01:00
rose net/rose: fix unbound loop in rose_loopback_timer() 2019-04-24 14:39:26 -07:00
rxrpc rxrpc: fix race condition in rxrpc_input_packet() 2019-04-24 14:05:09 -07:00
sched sch_cake: Make sure we can write the IP header before changing DSCP bits 2019-04-04 10:55:59 -07:00
sctp sctp: Check address length before reading address family 2019-04-12 10:25:03 -07:00
smc net/smc: move unhash before release of clcsock 2019-04-11 11:04:08 -07:00
strparser net: strparser: partially revert "strparser: Call skb_unclone conditionally" 2019-04-10 13:07:02 -07:00
sunrpc Fix miscellaneous nfsd bugs, in NFSv4.1 callbacks, NFSv4.1 2019-04-23 13:40:55 -07:00
switchdev switchdev: Remove unused transaction item queue 2019-03-01 21:35:19 -08:00
tipc tipc: set sysctl_tipc_rmem and named_timeout right range 2019-04-16 21:32:02 -07:00
tls net/tls: fix copy to fragments in reencrypt 2019-04-27 20:17:19 -04:00
unix io_uring-2019-03-06 2019-03-08 14:48:40 -08:00
vmw_vsock vsock/virtio: fix kernel panic from virtio_transport_reset_no_sock 2019-03-08 15:15:44 -08:00
wimax wimax: remove blank lines at EOF 2018-07-24 14:10:42 -07:00
wireless cfg80211: Notify previous user request during self managed wiphy registration 2019-04-23 13:45:30 +02:00
x25 net/x25: reset state in x25_connect() 2019-03-11 15:40:14 -07:00
xdp xsk: fix umem memory leak on cleanup 2019-03-16 01:27:51 +01:00
xfrm xfrm: Fix inbound traffic via XFRM interfaces across network namespaces 2019-02-18 10:58:54 +01:00
compat.c Merge branch 'timers-2038-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-03-05 14:08:26 -08:00
Kconfig net: devlink: turn devlink into a built-in 2019-02-26 08:49:05 -08:00
Makefile net: split out functions related to registering inflight socket files 2019-02-28 08:24:23 -07:00
socket.c net: add documentation to socket.c 2019-03-15 15:29:47 -07:00
sysctl_net.c